About this time duration calculator
Subtracting times by hand goes wrong easily, because minutes run to 60 and hours to 24. This calculator finds the exact time between a start and an end, down to the second. Within one day, an end time earlier than the start is treated as the next morning, so a 22:00 to 06:15 night shift gives 8 hours 15 minutes. Across dates, choose both days and it counts every hour in between. Results come as days, hours, minutes, and seconds, and as decimal hours, which payroll and timesheet systems usually need.
How to calculate a time duration
- Choose the mode. Pick Within one day, or Across dates and choose the start and end dates.
- Enter the times. Type the start and end time in 24-hour form, or press an example such as Night shift.
- Press Calculate duration. Read the duration and the totals in minutes, decimal hours, and workdays.
Frequently asked questions
How do I convert minutes to decimal hours?
Divide the minutes by 60. 8 hours 30 minutes is 8.5 decimal hours and 7 hours 45 minutes is 7.75. The Decimal hours result does this for you, which is the format most timesheets use.
What happens if the end time is earlier than the start?
Within one day, the end is read as the next day, so 22:00 to 06:15 is 8 hours 15 minutes. Across dates, an end that comes before the start shows an error instead.
How are workdays calculated?
The total hours are divided by 8, the length of a standard workday. A 40-hour span is 5 workdays. Breaks are not subtracted, so take them off the times first if needed.
Does daylight saving time change the result?
No. The calculator counts clock time as if every day had 24 hours. On the night clocks change, a shift can really be one hour longer or shorter than the result.